The present invention relates to rotary blade cutterbars and more particularly relates to support hubs for the idler gears of such cutterbars.
Rotary blade cutterbars have a plurality of side-by-side cutting units with the cutter discs of some cutterbars having gear pinion gears driven through a gear train comprising a plurality of meshed idler gears. These idler gears are meshed with each other so as to transmit power from one end to the other of the cutterbar and are selectively meshed with the pinion gears of the cutting units for determining the direction of rotation of the cutting units. The support hubs for the idler gears of one known cutterbar of this type are fabricated from steel and include o-ring grooves in which o-rings are placed to seal the interfaces of the hub with the gear box. These hubs experience very high shear loads at times when the cutting blades of the cutter units impact foreign objects in the field. Also, the current cutterbar transmits gear vibrations to the implement through its rigid structure and is heavy. U.S. Pat. No. 5,715,662, granted to Walters on Feb. 10, 1998 discloses a cutterbar of this type.
According to the present invention there is provided an improved rotary blade cutterbar of the type including a plurality of cutting units having pinion gears driven through a train of meshed idler gears, and more particularly there is provided improved hubs for mounting the idler gears.
An object of the invention is to provide a rotary blade cutterbar having idler gears with supporting hubs that are relatively light weight while being capable of dampening gear vibrations.
Another object of the invention is to provide idler gear supporting hubs, as set forth in the previous object, which are lower in cost than current idler gear supporting hubs yet strong enough to withstand high shear loads.
A specific object of the invention is to provide idler gear supporting hubs, as set forth in the previous objects, wherein the hubs are constructed of a molded plastic material.
Still a more specific object of the invention is to provide idler gear supporting hubs as set forth in the immediately preceding object wherein the hubs are each strengthened by a metal insert.
These and other objects of the invention will be apparent from a reading of the ensuing description together with the appended drawings.